Mojo C++ bindings: some MultiplexRouter optimization.

mojo/public/cpp/bindings/lib/multiplex_router.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_MULTIPLEX_ROUTER_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_MULTIPLEX_ROUTER_H_
 
 #include <stdint.h>
 
 #include <deque>
 #include <map>
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/ref_counted_delete_on_message_loop.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "mojo/public/cpp/bindings/callback.h"
 #include "mojo/public/cpp/bindings/lib/connector.h"
 #include "mojo/public/cpp/bindings/lib/interface_id.h"
 #include "mojo/public/cpp/bindings/lib/message_header_validator.h"
 #include "mojo/public/cpp/bindings/lib/pipe_control_message_handler.h"
 #include "mojo/public/cpp/bindings/lib/pipe_control_message_handler_delegate.h"
 #include "mojo/public/cpp/bindings/lib/pipe_control_message_proxy.h"
 #include "mojo/public/cpp/bindings/lib/scoped_interface_endpoint_handle.h"
 
+namespace base {
+class SingleThreadTaskRunner;
+}
+
 namespace mojo {
 
 class AssociatedGroup;
 
 namespace internal {
 
 class InterfaceEndpointClient;
 
 // MultiplexRouter supports routing messages for multiple interfaces over a
 // single message pipe.
@@ skipping 125 matching lines @@
 
   // Processes enqueued tasks (incoming messages and error notifications).
   // If |force_async| is true, it guarantees not to call any
   // InterfaceEndpointClient methods directly.
   //
   // Note: Because calling into InterfaceEndpointClient may lead to destruction
   // of this object, if |force_async| is set to false, the caller needs to hold
   // on to a ref outside of |lock_| before calling this method.
   void ProcessTasks(bool force_async);
 
-  // Returns true to indicate that |task| has been processed. Otherwise the task
-  // will be added back to the front of the queue.
+  // Returns true to indicate that |task|/|message| has been processed.
   bool ProcessNotifyErrorTask(Task* task, bool force_async);
-  bool ProcessIncomingMessageTask(Task* task, bool force_async);
+  bool ProcessIncomingMessage(Message* message, bool force_async);
 
+  void MaybePostToProcessTasks(base::SingleThreadTaskRunner* task_runner);
   void LockAndCallProcessTasks();
 
   // Updates the state of |endpoint|. If both the endpoint and its peer have
   // been closed, removes it from |endpoints_|.
   // NOTE: The method may invalidate |endpoint|.
   enum EndpointStateUpdateType { ENDPOINT_CLOSED, PEER_ENDPOINT_CLOSED };
   void UpdateEndpointStateMayRemove(InterfaceEndpoint* endpoint,
                                     EndpointStateUpdateType type);
 
   void RaiseErrorInNonTestingMode();
 
+  InterfaceEndpoint* FindOrInsertEndpoint(InterfaceId id, bool* inserted);
+
   // Whether to set the namespace bit when generating interface IDs. Please see
   // comments of kInterfaceIdNamespaceMask.
   const bool set_interface_id_namespace_bit_;
 
   MessageHeaderValidator header_validator_;
   Connector connector_;
   bool encountered_error_;
 
   base::ThreadChecker thread_checker_;
 
   // Protects the following members.
   mutable base::Lock lock_;
   PipeControlMessageHandler control_message_handler_;
   PipeControlMessageProxy control_message_proxy_;
 
   std::map<InterfaceId, scoped_refptr<InterfaceEndpoint>> endpoints_;
   uint32_t next_interface_id_value_;
 
   std::deque<scoped_ptr<Task>> tasks_;
 
+  bool posted_to_process_tasks_;
+
   bool testing_mode_;
 
   DISALLOW_COPY_AND_ASSIGN(MultiplexRouter);
 };
 
 }  // namespace internal
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_MULTIPLEX_ROUTER_H_